【摘要】 以PLA/PLGA等三种高分子聚合物为载体,以LNG为活性药物的微球长效避孕注射剂,进行了体内、外释药速率、载体的体内降解以及抑制大鼠动情周期的比较研究。实验结果认为三种微球注射剂均具有明显延缓药物释放的性能,其释药和聚合物降解速度随LA比例的减小而增快,但体外释放及抑制大鼠性周期的天数则无明显差别。更多还原

【Abstract】 This paper describes that the release rate, the biodegradation of polymer and the estrus suppression of three kinds of polymer microspheres containning LNG in vitro and in vivo. The release test in vivo was carried out in female rats by intramuscular injection of microspheres and the serum LNG levels were analysed by RIA. The effect of estrus suppression in rats were observed with vaginal smear examination. The results showed that LNG release from microspheres were slower than the microcrystal of LNG. With the increase of LA proportion of PLGA, the LNG release rate of microspheres decreased. The biodegradation test of polymer indicated that PLGA degraded much faster than PLA and the degradation rate was significantly enhanced with the increase of glycolic acid(GA) content in copolymers.更多还原